ABSTRACT
OBJECTIVE: To investigate the change of indicators of oxidative stress in serum and NF-kappaB in peripheral blood mononuclear cells of patients with silicosis, and explore the mechanism of the development of silicosis. METHODS: The subjects were divided into (1) 200 workers exposed to SiO2 for at least 1 years in a foundry served as the dust-exposure group; (2) 130 cases with silicosis (I phase silicosis 64 cases, II phase 46 cases III phase 20 cases) served as the silicosis group; (3) 32 cases with 0+ phase silicosis in the foundry served as the observed group,(4)100 subjects from a hotel served as the control group. The serum including superoxide dismutase (SOD), nitric oxide (NO), serum glutathione peroxidase (GSH-Px), total antioxidant capacity (T-AOC), nitric oxide synthase (NOS), lipid malondialdehyde (MDA) and NF-kappaB protein levels in peripheral blood mononuclear cells were determined, respectively. RESULTS: Compared with the control group, NO levels in dust-exposed group and silicosis group significantly increased, and SOD decreased significantly (P < 0.05 or P < 0.01). Compared with the control group and dust-exposed group, T-AOC, NOS, MDA levels in silicosis group significantly increased (P < 0.05 or P < 0.01). GSH-Px in dust-exposed group and silicosis group were (231.164 +/- 36.484) and (270.469 +/- 39.228)U/ml, respectively which were significantly than that [(223.360 +/- 46.838) U/ml] in control group (P < 0.05 or P < 0.01), and there was significant difference of GSHPx between the silicosis group and the dust-exposed group significantly (P < 0.01) . GSH-Px level [(290.750 +/- 39.129) U/ml] in III phase silicosis group were significantly higher than those [(256.906 +/- 21.41) and (259.594 +/- 34.79) U/ml] in observation group and I phase silicosis group (P < 0.05). NF-kappaB levels [(72.06 +/- 9.12) and (85.25 +/- 11.64) ng/L] in dust-exposed group and silicosis group were significantly higher than that [(59.71 +/- 9.27) ng/L] in control group (P < 0.01), and there was significant difference of between the silicosis group and the dust-exposed group (P < 0.01). There was a positive correlation between serum GSH-Px level and the silicosis stages (r = 0.507, P < 0.01). Also there was a positive correlation between NF-kappaB level and silicosis stages, age, GSH-Px or NO levels (r = 0.376, 0.243, 0.233, 0.221, P < 0.01). CONCLUSION: The imbalance of oxidative and anti-oxidation system and the activation of NF-kappaB are related with the occurrence and development of silicosis. The monitoring of oxidative stress indicators and NF-kappaB is beneficial to the prediction and prognosis assessment of silicosis.
